steamingpile:born_yesterday: steamingpile: Yeah if you have a kill shelter then try and find one there, always felt sad doing networks in there and leaving dogs. Make sure you get one fairly young, don't need a headache someone dumped off.

Like my dad's dog, whose original owner apparently beat her with a fishing rod.

Yeah, dad, don't think that's working. Pretty sure the dog doesn't speak conversational English. Just get her to stop growling and snapping at me, would ya?

/Last cat was a stray.//Would never go to a pet mill.

How big is the dog and how big are you? The easiest way is to try the dominance method where you get near them and lie down on them until they quit trying to get up and submit. It is a dominance issue that will let a dog know who they are supposed to submit to instead of being a dick.

NO. DON'T DO THIS. People commonly recommend it and maybe it has worked on some dogs, but in general it puts you in danger of being bitten, and frightens the dog, reinforcing its need to be aggressive around you (most aggression is fear based, not dominance based). Imagine if some scary person came into your house and you told him to GTFO and he grabbed you and tried to hold you down on your back to "show you you have to submit". You'd flip the f*ck out and think you're going to die. This method would best be described as "flooding" and only works if you can safely (for you and the dog) restrain him for as long as it takes for him to become completely calm. It's akin to teaching a person not to be afraid of spiders by locking them up in a box with spiders and not letting them out until they are calm. You can do it that way, but it's torture, they may hurt themselves or someone else trying to escape in a panic, and if you stop even a little bit before they have fully calmed down you've only increased their fear. It's a bad idea.

The best way to handle this would be to have your dad talk to his vet or a good trainer (one who uses primarily non-punishment based methods) about desensitization exercises. Without knowing the triggers or how severe the aggression is, I can't give very specific advice. The dog needs to learn that visitors are okay and what appropriate behaviour is expected when they come around. For some dogs this is as simple as having visitors ignore him and drop treats periodically without making eye contact or approaching him until he comes up to them willingly. For others, you may need to have the owner restrain the dog and start with visitors outside, slowly working your way up to having them enter the house.